Mask system and method for constructing the same

ABSTRACT

A mask system including a frame module and a cushion module provided to the frame module and adapted to form a seal with the patient&#39;s face. The cushion module includes a main body defining a breathing chamber and adapted to interface with the frame module and a cushion adapted to form a seal with the patient&#39;s face. The main body and the cushion are comolded with one another.

CROSS-REFERENCE TO APPLICATION

This application is a continuation of U.S. application Ser. No.14/555,244, filed Nov. 26, 2014, which is a divisional of U.S.application Ser. No. 12/379,940, filed Mar. 4, 2009, which claims thebenefit of U.S. Provisional Application Nos. 61/064,407, filed Mar. 4,2008, and 61/136,488, filed Sep. 9, 2008, each of which is incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a mask system used for treatment, e.g.,of Sleep Disordered Breathing (SDB) with Continuous Positive AirwayPressure (CPAP) or Non-Invasive Positive Pressure Ventilation (NIPPV).

BACKGROUND OF THE INVENTION

Patient interfaces, such as a full-face or nasal mask systems, for usewith blowers and flow generators in the treatment of sleep disorderedbreathing (SDB), typically include a soft face-contacting portion, suchas a cushion, and a rigid or semi-rigid shell or frame. In use, theinterface is held in a sealing position by headgear so as to enable asupply of air at positive pressure (e.g., 2-30 cm H₂O) to be deliveredto the patient's airways.

One factor in the efficacy of therapy and compliance of patients withtherapy is the comfort and fit of the patient interface.

The present invention provides alternative arrangements of mask systemsto enhance the efficacy of therapy and compliance of patients withtherapy.

SUMMARY OF THE INVENTION

One aspect of the invention relates to a mask system including a framemodule and a cushion module provided to the frame module and adapted toform a seal with the patient's face. The cushion module includes a mainbody defining a breathing chamber and adapted to interface with theframe module and a cushion adapted to form a seal with the patient'sface. The main body and the cushion are comolded with one another.

Another aspect of the invention relates to a mask system including acushion module including a main body defining a breathing chamber and acushion adapted to form a seal with the patient's face, and an elbowmodule provided to the cushion module and adapted to be connected to anair delivery tube that delivers breathable gas to the patient. The mainbody and the cushion are comolded with one another.

Another aspect of the invention relates to a kit including a framemodule, at least first and second cushion modules adapted to be providedto the frame module and adapted to form a seal with the patient's face,and an elbow module adapted to be provided to each of the at least firstand second cushion modules and adapted to be connected to an airdelivery tube that delivers breathable gas to the patient. The at leastfirst and second cushion modules are different from one another in atleast one aspect.

Another aspect of the invention relates to a method for constructing amask system including molding a relatively hard part of a cushionmodule, co-molding a relatively soft part of the cushion module to therelatively hard part, and using an automated robot, grasping therelatively hard part and assembling the co-molded cushion module toanother component of the mask system.

Another aspect of the invention relates to a method for fitting a masksystem to a patient including providing a frame module, selecting acushion based on a preferred cushion style, attaching a cushion modulewith the selected cushion to the frame module, selecting a vent styleand/or impedance requirement, and attaching an elbow module with theselected vent style and/or impedance requirement to the cushion module.

Another aspect of the invention relates to a mask system including aframe module, a cushion module provided to the frame module and adaptedto form a seal with the patient's face, an elbow module adapted to beconnected to an air delivery tube that delivers breathable gas to thepatient, and a dynamically adjustable connector provided between theframe module and the cushion module and/or between the elbow module andthe frame module or the cushion module. Other locations of thedynamically adjustable connector are possible.

Another aspect of the invention relates to a mask system including aframe and a forehead support provided to a base of the frame by amovement region structured to allow adjustment of the frame relative tothe forehead support.

Other aspects, features, and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1-1 is a front perspective view of a mask system according to anembodiment of the present invention;

FIG. 1-2 is a front view of the mask system shown in FIG. 1-1;

FIG. 1-3 is a side view of the mask system shown in FIG. 1-1;

FIG. 1-4 is a bottom view of the mask system shown in FIG. 1-1;

FIG. 2 is an exploded view of the mask system shown in FIG. 1-1;

FIG. 3-1 is a rear perspective view of a frame module of the mask systemshown in FIG. 1-1;

FIG. 3-2 is a side view of the frame module shown in FIG. 3-1;

FIG. 4-1 is a front perspective view of a cushion module of the masksystem shown in FIG. 1-1;

FIG. 4-2 is a rear perspective view of the cushion module shown in FIG.4-1;

FIG. 4-3 is a side view of the cushion module shown in FIG. 4-1;

FIG. 4-4 is an exemplary cross-sectional view through the cushion moduleaccording to an embodiment of the present invention;

FIG. 4-5 is a schematic view illustrating the cushion module pivotallymounted to the frame module according to an embodiment of the presentinvention;

FIG. 4-6 is a schematic view illustrating a locking arrangement forcoupling the cushion module to the frame module according to anembodiment of the present invention;

FIG. 4-7 is a side view of a mask system including a flexible memberaccording to an embodiment of the present invention;

FIG. 4-8 is a side view of a mask system including a flexible memberaccording to another embodiment of the present invention;

FIG. 4-9 is a perspective view of a mask system including flexiblemembers according to another embodiment of the present invention;

FIG. 4-10 is an exploded view of the mask system shown in FIG. 4-9;

FIG. 4-11 is a perspective view of a mask system including flexiblemembers according to another embodiment of the present invention;

FIG. 4-12 is a perspective view of a mask system including a continuousflexible member according to another embodiment of the presentinvention;

FIG. 4-13 is a front view of a frame and forehead support according toan embodiment of the present invention;

FIG. 4-14 is a partial perspective view of the forehead support of FIG.4-13;

FIG. 4-15 is a side view showing coarse adjustment of the frame andforehead support of FIG. 4-13;

FIG. 4-16 is a side view showing fine adjustment of the frame andforehead support of FIG. 4-13;

FIG. 4-17 is a side view showing a co-molded base of the foreheadsupport of FIG. 4-13 according to an embodiment of the presentinvention;

FIG. 4-18 is a cross-sectional view showing the base of a foreheadsupport detachably connected to a frame according to an embodiment ofthe present invention;

FIG. 5-1 is a front perspective view of an elbow module of the masksystem shown in FIG. 1-1;

FIG. 5-2 is a rear perspective view of the elbow module shown in FIG.5-1;

FIG. 5-3 is a side view of the elbow module shown in FIG. 5-1;

FIG. 6 is a front perspective view of the mask system shown in FIG. 1-1with the elbow module arranged in a different orientation;

FIG. 7 is a schematic view of a cushion module, elbow module, and ventmodule according to another embodiment of the present invention;

FIGS. 8-1 and 8-2 are cross-sectional views showing an elbow moduleattachment according to an embodiment of the present invention; and

FIG. 9 is a cross-sectional view showing an elbow module attachmentaccording to another embodiment of the present invention.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The following description is provided in relation to several embodimentswhich may share common characteristics and features. It is to beunderstood that one or more features of any one embodiment may becombinable with one or more features of the other embodiments. Inaddition, any single feature or combination of features in any of theembodiments may constitute additional embodiments.

While each embodiment below is described as including a nasal interfacetype, each embodiment may be adapted for use with other suitableinterface types. That is, the interface type is merely exemplary, andeach embodiment may be adapted to include other interface types, e.g.,full face interface, etc.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

The term “air” will be taken to include breathable gases, for exampleair with supplemental oxygen.

1. Mask System

FIGS. 1-1 to 1-4 and 2 illustrate a mask system 10 according to anembodiment of the present invention. In this embodiment, the mask system10 includes a nasal interface. The mask system 10 includes a framemodule 20, a cushion module 40 provided to the frame module 20 andadapted to form a seal with the patient's face, and an elbow module 70provided to the cushion module 40 and adapted to be connected to an airdelivery tube (not shown) that delivers breathable gas to the patient.Headgear may be removably attached to the frame module 20 to maintainthe mask system 10 in a desired adjusted position on the patient's face.The mask system 10 is intended for use in positive pressure therapy forusers with obstructive sleep apnea (OSA) or another respiratorydisorder.

As described below, the mask system 10 provides a modular design thatallows different styles and/or sizes of the frame module 20, cushionmodule 40, and elbow module 70 to be interchanged or mixed and matchedwith one another to provide a more customized mask system for thepatient. In addition, such design allows selected modules to be easilyreplaced, e.g., treatment requirements change, worn out or damaged, etc.

1.1 Frame Module

The frame module 20 is structured to maintain the cushion module 40 inan operative position with respect to the patient's face. In addition,the frame module 20 is structured to removably attach to headgearadapted to maintain the mask system 10 in a desired position on thepatient's face.

As best shown in FIGS. 2 and 3-1 to 3-2, the frame module 20 includes anopen construction that provides an annular cushion retaining portion 22structured to retain the cushion module 40. The frame module 20 may alsoinclude one or more additional components, such as a fixed foreheadsupport 30 that extends from a top of the cushion retaining portion 22,and/or headgear connectors 24 provided to respective sides of thecushion retaining portion 22. Headgear connectors 32 may be provided torespective sides of the forehead support 30. Each headgear connector 24,32 has at least one slot adapted to receive a respective headgear strapin use.

The frame module 20 may be constructed from a wide range of materials(e.g., polycarbonate, polypropylene, thermoplastic elastomer (TPE),Pocan®, etc.) and may include styling options for comfort and/oraesthetics. For example, the frame module 20 may be constructed of TPE,which provides a relatively soft structure, coloring options,flexibility, and gripping options. In another embodiment, TPE may beovermolded to one or more portions of the frame module 20, e.g., alongforehead support, etc. In another embodiment, the frame module 20 mayinclude flocking to provide softness, coloring, textured gripping, etc.Also, an in-mold design may be provided to the frame module 20, e.g.,logo and/or aesthetic features integrally molded with the frame module.

In the illustrated embodiment, each headgear connector 24 includes anarm 26 that is suitably contoured so as to engage a respective cheek ofthe patient in use. As indicated in dashed lines in FIG. 3-1, a cheekpad 28 (e.g., constructed of TPE) may be provided to the inner surfaceof the arm 26 to support the arm 26 on the patient's cheek and stopbottoming out of the frame module 20 on the patient's face in use.

1.1.1 Forehead Support

The forehead support 30 provides a support and stability mechanismbetween the mask system 10 and the patient's forehead. The foreheadsupport 30 has a general “T”-shape, with a base 34 and a pair of arms 36arranged along the upper cross portion of the “T”. Each arm 36 supportsan elastomeric or foam forehead pad 38 that is structured to engage apatient's forehead in use. In addition, each end of the arm 36 providesa headgear connector 32 (e.g., slot) adapted to receive a respectiveheadgear strap.

In the illustrated embodiment, the forehead support 30 has asubstantially fixed setting. However, as shown in FIG. 3-2, the base 34of the forehead support 30 is contoured along its length and may includesome inherent flexibility to allow a range of adjustment. Also,adjustment may be provided by adjusting the position of the cushionmodule 40 with respect to the frame module 20 as described in greaterdetail below. However, the forehead support 30 may be structured toinclude some form of mechanical adjustment.

In an alternative embodiment, the frame module 20 may not include aforehead support, and additional headgear connectors may be provided tothe cushion retaining portion 22 to receive respective headgear straps,e.g., upper and lower headgear connectors on each side of the cushionretaining portion.

1.1.2 Headgear Attachment

Headgear may be removably attached to the headgear connectors 32 of theforehead support 30 and the headgear connectors 24 of the cushionretaining portion 22 to maintain the mask system 10 in a desiredposition on the patient's face.

For example, the headgear may include a pair of upper and lower strapswith the upper straps removably connected to headgear connectors 32provided on the forehead support 30 and the lower straps removablyconnected to headgear connectors 24 provided on the cushion retainingportion 22. However, headgear straps may be secured to the frame module20 in other suitable manners, e.g., clip arrangement, adjustableladder-lock arrangement, etc.

In an embodiment, the headgear may include a similar headgeararrangement as that disclosed in PCT application no. PCT/AU2006/000770,filed Jun. 6, 2006, which is incorporated herein by reference in itsentirety.

In an alternative embodiment, the headgear may be molded (e.g., fromTPE). In such arrangement, forehead pads may be incorporated into themolded upper straps of the headgear.

1.1.3 Frame Module Profile

As illustrated, the frame module 20 has a low profile when viewed fromthe side (e.g., see FIGS. 1-3 and 3-2). That is, the frame module 20 iscontoured so that it closely follows the contours of the patient's face.In use, the frame module 20 is substantially flush with the patient'sface and does not substantially protrude from the patient's face. As aresult, the frame module 20 is less obtrusive and does not significantlyaffect the patient's field of view.

1.2 Cushion Module

The cushion module 40 is structured to interface with the frame module20 and form a seal with patient's nose in use. In addition, the cushionmodule 40 is structured to maintain the elbow module 70 in an operativeposition.

As best shown in FIGS. 2 and 4-1 to 4-3, the cushion module 40 includesa main body 42 and a cushion 44 provided to the main body 42. The mainbody 42 is constructed of a relatively rigid material (e.g.,polycarbonate) and the cushion 44 is constructed of a relatively softelastomeric material (e.g., silicone or foam). In use, the main body 42defines a breathing chamber and is adapted to interface with orotherwise attach to the frame module 20 and the cushion 44 is adapted toform a seal with the patient's nose. Also, the main body 42 includes anopening 46 that is adapted to interface with or otherwise attach to theelbow module 70.

In the illustrated embodiment, the cushion 44 is a nasal cushion adaptedto engage the patient's face generally along nasal bridge, cheek, andupper lip regions of the patient's face. As shown in FIG. 4-2, thecushion 44 includes a base wall 44(1) provided to the main body 42, anundercushion layer (UCL) 44(2) extending away from the base wall 44(1),and a membrane 44(3) provided to substantially cover the UCL 44(2) andprovide a sealing structure. In an embodiment, the cushion 44 mayinclude a cushion structure similar to that disclosed in PCT applicationno. PCT/AU2006/000032, filed Jan. 12, 2006, which is incorporated hereinby reference in its entirety. However, other cushion interfaces andstructures are possible, e.g., full-face.

Also, the mask system 10 may be provided with a number of differentcushion modules 40, e.g., each having cushions of different stylesand/or sizes (e.g., depending on patient preference and/or fit). Forexample, the main body 42 of each cushion module may include a common oruniversal configuration for use with the frame module 20, and thecushion 44 may include different styles and/or sizes. This provides amodular arrangement that allows the frame module 20 to be selectivelyand removably coupled to one of multiple cushion modules. For example,the different cushion modules may include different size cushions (e.g.,small, medium, and large) and may include a different cushionstructures.

Similarly, the cushion module 40 may be provided with different framemodules 20, e.g., each frame module having a different style and/or size(e.g., frame module without forehead support, frame module withdifferent arrangement/style of headgear connectors, etc).

1.2.1 Co-Molding

In the illustrated embodiment, the main body 42 and cushion 44 areco-molded with one another to form a one-piece, integrated component.For example, the main body 42 may be molded of a relatively rigidmaterial (e.g., polycarbonate) and the cushion 44 may be co-molded ontothe main body 42 of a relatively soft elastomeric material (e.g.,silicone).

In an embodiment, the main body 42 may be molded from a hightemperature, biocompatible polycarbonate structured to maintain itsstructure (e.g., Bayer Apec 1745 polycarbonate). The cushion 44 may becomolded to the main body 42 from a silicone material that is able tochemically bond or self-adhere to the polycarbonate material of the mainbody 42 (e.g., Shinetsu KE-2090-40 Duro silicone). In an embodiment, thesilicone cushion 44 may have a uniform thickness to reduce materialusage and provide faster cycle times. However, other suitable materialsare possible.

The outer perimeter of the main body 42 provides an interfacingstructure 48 (e.g., land area) structured to bond with the base wall44(1) of the cushion 44. In an embodiment, the interfacing structure 48may provide the minimum land area to achieve an adequate bond with thecushion 44. Such bond may be made stronger by increasing the land area.

In an embodiment, flow bias of the mold material may be utilized whenforming the cushion module 40. For example, FIG. 4-4 is an exemplarycross-sectional view illustrating the cushion 44 co-molded to the mainbody 42. As illustrated, the interfacing structure 48 may include aprojection 48(1) structured to provide sufficient land area to bond withthe cushion base wall 44(1). As material first flows into the path ofleast resistance during molding, an inner portion 44(1)-1 of the cushionbase wall 44(1) may be designed to be thicker than an outer portion44(1)-2 of the cushion base wall 44(1) (e.g., 20-40% thicker) somaterial flows first into the mold for the inner portion 44(1)-1 beforeit flows into the mold for the outer portion 44(1)-2. This arrangementforces air in the direction of the outer portion 44(1)-2 to ensure acomplete part with no air trapped in the mold for the inner portion44(1)-1.

Co-molding the main body 42 to the cushion 44 provides a chemical bondwithout a mechanical interlock. As a result, the connection includes nocracks, a gas tight seal, and clean interface. Moreover, such co-moldedconnection relaxes tolerances as the mold materials are sufficientlyflexible to fill in any gaps at the interface between the main body 42and the cushion 44.

1.2.2 Automated Manufacturing

The co-molded cushion module 40 also facilitates automatedmanufacturing. That is, the co-molded cushion module 40 includes arelatively hard part (i.e., the main body 42) and a relatively soft part(i.e., the cushion 44), and the relatively hard part is easier to handleand manipulate during assembly. For example, an automated robot maygrasp the hard part of the cushion module 40 to manipulate the same forassembly to the frame module 20. Typically, cushion components aredifficult to grasp with an automated robot (e.g., due to its relativesoftness) and require manual assembly to a relatively rigid frame. Thecushion module 40 allows the entire mask system to be roboticallyassembled as each component of the mask system (i.e., frame module 20,cushion module 40, elbow module 70) includes a relatively hard part thatcan be gripped by an automated robot. In an alternative embodiment, eachmask component may include other suitable structure to facilitategripping by an automated robot, e.g., a relatively thick siliconeportion that could be gripped by a robot.

In an embodiment, a method for making and assembling the mask system 10may include molding the relatively hard part (i.e., the main body 42) ofthe cushion module 40, inserting the hard part into a silicone mold by arobot, injecting or otherwise molding the relatively soft part (i.e.,the silicone cushion 44) to the relatively hard part, removing theco-molded cushion module 40 from the mold by a robot, and assembling thecushion module 40 to the remaining components of the mask system 10,i.e., all of which have a relatively hard part that can be gripped by arobot.

1.2.3 Cushion Module Attachment to Frame Module

The frame module 20 is structured to maintain the cushion module 40 inan operative position with respect to the patient's face.

In the illustrated embodiment, the annular cushion retaining portion 22includes a flange or interfacing structure 23 (e.g., see FIG. 3-1) alongits peripheral edge that is adapted to interface with or otherwiseremovably connect to the interfacing structure 48 along the outerperimeter of the main body 42 of the cushion module 40. The interfacingstructures 23, 48 may connect with a friction fit, snap-fit, mechanicalinterlock, or other suitable attachment mechanism. However, othersuitable arrangements for attaching the cushion module 40 to the framemodule 20 are possible.

For example, the cushion module 40 may be coupled to the frame module 20in a manner that allows the cushion module 40 to be locked in differentangular positions with respect to the frame module 40. This arrangementallows the cushion module 40 to be selectively angled to enhance seal,comfort, adjust positioning of forehead support, etc.

For example, as shown in FIG. 4-5, the cushion module 40 may bepivotally mounted to the frame module 20 (e.g., via pivot 102), and thecushion module 40 may include one or more locking lugs or a ratchet/geararrangement 104 to lock the cushion module 40 to the frame module 20 indifferent angular positions. It should be appreciated that the locationof the pivot/lugs may be reversed, and that the pivoting/lockingarrangement may include other suitable structures.

In an alternative embodiment, as shown in FIG. 4-6, the cushion module40 may include protrusions 106 that are adapted to interlock withselected recesses 108(1), 108(2), 108(3) provided to the frame module 20(i.e., recesses oriented at different heights, angles, etc.) to changethe positioning or angle of the cushion module 40 with respect to theframe module 20. It should be appreciated that the number and placementof the protrusions/recesses may be changed.

In another alternative embodiment, a biasing arrangement may be providedbetween the frame module 20 and cushion module 40 to provide a biasingforce between the frame module 20 and the cushion module 40. Suchbiasing force may bias the cushion module 40 into the patient's face inuse, e.g., to enhance seal.

In another embodiment, the mask system may be self-fitting so that thecushion module 40 is structured to self adjust as it is positioned intoengagement with the patient's face. Such self-fitting mask system mayalso be manually adjustable and/or lockable by the patient.

FIGS. 4-7 to 4-11 illustrate alternative embodiments of a self-fittingmask system in which one or more flexible members join the cushionmodule to the frame module. In use, the one or more flexible members arestructured to allow adjustment of the cushion module with respect to theframe module, i.e., flexible members add flexibility and articulation ofthe cushion module with respect to the frame module. That is, thecushion module can selectively adjust and/or self-fit to the patient'sface against biasing from the one or more flexible members.

The one or more flexible members define a dynamically adjustableconnector to decouple rigid connections (e.g., cushion to frame) andallow substantially free, self-fitting adjustment. It should beappreciated that such a dynamically adjustable connector may be providedbetween other suitable components of the mask system (e.g., betweenframe and elbow, between frame and headgear connectors, etc.). FIGS. 8-1to 9 described below relate to a gusset arrangement between the elbowand frame/cushion module to enhance flexibility and reduce tube drag.

In the embodiment of FIG. 4-7, a lower end of the cushion module 240 ispivotally mounted to the frame module 220 (e.g., via pivot 202), and anupper end of the cushion module 240 is coupled to the base 234 of theforehead support 230 by at least one flexible member 260. Asillustrated, the base 234 of the forehead support 230 includes a seriesof spaced apart protrusions or locking lugs 204 along its length thatallows the flexible member 260 to be retained in different positions onthe base 234, e.g., to adjust the biasing force provided by the flexiblemember 260 and/or adjust the initial position or angle of the cushionmodule 240 with respect to the frame module 220.

In the embodiment of FIG. 4-8, a lower end of the cushion module 340 ispivotally mounted to the frame module 320 (e.g., via pivot 302), and anupper end of the cushion module 340 is coupled to a lower end of thebase 334 of the forehead support 330 by at least one flexible member360. The cushion module 340 includes a lip 341 to support one end of theflexible member 360 while the opposite end of the flexible member 360 issupported by the lower end of the base 334. In the illustratedembodiment, the flexible member 360 is oriented substantiallyperpendicular to the patient's face in use.

In the embodiment of FIGS. 4-9 and 4-10, an upper end of the cushionmodule 440 is coupled to the base 434 of the forehead support by aflexible member 460(1), and opposing sides of the cushion module 440 arecoupled to respective arms 426 of the frame module 420 by flexiblemembers 460(2), 460(3). In the illustrated embodiment, each flexiblemember 460(1), 460(2), 460(3) includes a flexible arm portion 462 and ahead portion 464 provided to the free end of the arm portion 462. Thebase 434 and arms 426 each include a tapered opening for removablysecuring a respective head portion 464 of the flexible members 460(1),460(2), 460(3) in position.

In the embodiment of FIG. 4-11, an upper end of the cushion module 540is coupled to the base 534 of the forehead support 530 by a flexiblemember 560(1), and opposing sides of the cushion module 540 are coupledto respective arms 526 of the frame module 520 by respective flexiblemembers (only the flexible member 560(2) being visible in FIG. 4-11). Inthe illustrated embodiment, each flexible member has a web-likeconfiguration that tapers from the cushion module to its attachment tothe forehead support/frame.

FIG. 4-12 illustrates an alternative version of FIG. 4-11. In thisembodiment (indicated with similar reference numerals to FIG. 4-11), thethree web-like flexible members are replaced by a single, continuousflexible member or “trampoline-like” membrane 560. As illustrated, thesingle, continuous flexible member 560 is a continuous piece or web thatextends around the perimeter of the cushion module 540 to connect thecushion module to the frame module 520. The single, continuous flexiblemember 560 may be connected to the frame module 520 in one or morelocations, e.g., coupled to the base 534 of the forehead support 530 andrespective arms 526 of the frame module 520. The single, piece web orflexible member may act like a gusset (e.g., similar to ResMed's Activamask), but it is secured at one or more points on the frame, so it hasthe benefits of a gusset while also providing the benefits of a dynamicadjustable connector.

In each embodiment, the cushion module may be adjusted or flexed from aminimum position (i.e., the position of the cushion module when no forceis applied to the cushion module by the patient) to a maximum position(i.e., the position of the cushion module when the patient applies forceto the cushion module until the cushion module can move no further withrespect to the frame module). The maximum position may be imposed by theframe module (e.g., the cushion module engages the frame module so itcannot extend past the frame module) or by the one or more flexiblemembers (e.g., the spring force of the one or more flexible members willnot allow further adjustment of the cushion module).

There are an infinite number of cushion module positions between theminimum and maximum positions because the flexible member is elastic.Additionally, there are no locking mechanisms in place to restrict orlimit the movement of the cushion module between the minimum and maximumpositions.

The one or more flexible members ensure that the angle of the cushionmodule is optimal for sealing engagement with a patient's face as itwill flex to align the cushion module to match the shape or angle of thepatient's face. The one or more flexible members may be positioned suchthat forces applied to the cushion module by the flexible member(s) willurge or bias the cushion module towards the patient's face, therebyenhancing the seal. For example, the one or more flexible members may bepositioned such that the distance between the cushion module and theframe module is at a maximum position and the one or more flexiblemembers are stretched. Thus, when the cushion module is applied to theface, the spring force of the elastic flexible member(s) will urge thecushion module against the face of the user.

The one or more flexible members may be connected from any position onthe cushion module to any position on the frame module/forehead support.For example, the flexible member(s) may be connected from the top of thecushion module to the base of the forehead support (see FIGS. 4-7 and4-8) and/or the flexible member(s) may be connected from the side of thecushion module to the frame module (see FIGS. 4-9 to 4-11).

The one or more flexible members may be permanently attached to thecushion module and/or frame module/forehead support by any suitablemeans, e.g., gluing, welding, co-molding. Alternatively, the one or moreflexible members may be temporarily or releasably attached to thecushion module and/or frame module/forehead support by any suitablemeans, e.g., mechanical connection, interference fit, snap fit, hook andloop.

The length of each flexible member may be adjustable so that the patientcan vary the elasticity of the flexible member. This may be advantageousin increasing or decreasing the spring force applied to the cushionmodule, resulting in varied forces on the patient's face. For example,the patient may wish to increase the force of the cushion module ontheir face so may increase the tension in the one or more flexiblemembers to increase the elastic or spring force on the cushion module.

The width of each flexible member may be about 1-100 mm. In anembodiment, each flexible member may be no wider than the frame moduleso as to avoid interfering with the patient's line of sight and also toreduce the obtrusiveness of the mask system. In another embodiment, thewidth of each flexible member may not be uniform, e.g., width of theflexible member varies along its length (e.g., hourglass shaped). Thisarrangement may be provided to vary the elastic properties of theflexible member.

Each flexible member may be composed of any material or combination ofmaterials that allow the desired level of flexibility, elasticity, orspring constant. For example, each flexible member may be one piece madefrom silicone, may include a combination of materials, or may includethe same material with different properties.

In the illustrated embodiment, one or more flexible members may join thecushion module to the frame module (e.g., one flexible member in FIGS.4-7 and 4-8 and three flexible members in FIGS. 4-9 to 4-11). Additionalflexible members increase the fit range of the mask system as it isbetter able to adjust to the patient's face in use.

FIGS. 4-13 to 4-18 illustrate a self-fitting or auto-adjusting masksystem according to another embodiment of the present invention. Whilethe illustrated embodiment is in the form of a nasal mask, it should beappreciated that aspects of the invention may be adapted for use withother suitable interface types, e.g., full-face mask.

As illustrated, the mask system includes a frame 820 (e.g., constructedof rigid or semi-rigid material such as polycarbonate, polypropylene,etc.) and a forehead support 830 provided to the frame 820. The frame820 provides a frame interface 821 adapted to support a flexible cushion840 that forms a seal with the patient's face in use. The frameinterface 821 may be relatively flat or planar, which may facilitateattachment (e.g., permanent (e.g., frame and cushion co-molded) orremovable connection) to cushions of different configurations and/ormaterials (e.g., gel cushion, foam cushion, silicone cushion (e.g.,silicone cushion with dual walls)). The frame 820 also provides an elbowinterface 823 adapted to support an elbow 870.

The forehead support 830 is coupled to the base of the frame 820 by amovement region 835 which allows the frame 820 to flex, bend and/orpivot relative to the forehead support 830. Such movement allowsadjustment of the frame 820 relative to the forehead support 830 toenhance comfort and seal of the mask system. Region 835 extends from thebase of the frame and upwards towards the forehead support 830.

In the illustrated embodiment, the forehead support 830 is generallyt-shaped. The base of the t-shaped forehead support may include spacedapart support members 834 that extend from the movement region 835. Asshown in FIG. 4-13, the support members 834 bifurcate about the elbowinterface 823 that supports the elbow. Such forehead support provides aminimalist arrangement to provide unobtrusiveness. However, the foreheadsupport may have other suitable configurations, e.g., I-shaped.

The upper cross portion of the t-shaped forehead support may include apair of downwardly extending arm bars 836 (although the arm bars maypotentially extend upwardly). The arm bars 836 may engage with headgearstraps so as to position the forehead support 830 on the forehead of thepatient and secure it in place. The arm bars 836 may also engage withheadgear straps with clips, ladder locks, or any other suitableattachment mechanism.

The forehead support 830 extends from the base or bottom of the frame820, which is adjacent the patient's mouth in use. For example, the baseof the frame 820 may be positioned near the patient's upper lip in anasal mask system, or the base of the frame 820 may be positioned nearthe patient's lower lip in a full-face mask system, or the movementregion 835 may extend from below the apex a (e.g., see FIG. 4-13) of theframe, e.g., near or below the elbow interface 823. The top or apex ofthe frame is positioned near the patient's nasal bridge region in bothnasal and full-face mask systems (although the apex of the frame couldalso be positioned lower down the patient's nose).

The movement region 835 extends generally along a length of the base ofthe forehead support, e.g., along region r shown in FIG. 4-15. However,it should be appreciated that the movement region may extend along theentire length of the base of the forehead support or one or moreselected portions of the forehead support. Also, region r may beconfined to an even smaller extent, e.g., only at the base. It should benoted that relatively small movement (m) near the base can result in arelatively large movement (M) of the forehead support (see FIG. 4-15),e.g., M may be 2-10×m or more. In an embodiment, a movement region maybe provided adjacent the arm bars 836 to allow the arms bars to flex,bend and/or pivot relative to support members 834.

The movement region 835 is contoured along its length and includessuitable dimensions (e.g., thickness) to provide flexing, bending and/orpivoting and allow a range of adjustment. In an embodiment, the movementregion may be in the form of a spring arm or may be a pivot joint with aspring to bias the forehead support 830 in the desired direction, e.g.,as shown in FIG. 4-15.

The location of the movement region 835 along a lower region of theframe, e.g., within the region r shown in FIG. 4-15, allows the foreheadsupport to force the frame into the patient's face as described below.

In the illustrated embodiment of FIG. 4-15, the forehead support 830 ismolded in one piece (e.g., co-molded) with the base of the frame 820(i.e., at the movement region 835) to facilitate flexibility andmovement in this area. The forehead support 830 may be made from apolymer such as polycarbonate, polypropylene, nylon, TPE, etc.

An upper strap 890 of the headgear can be positioned around the head ofthe patient and through the upper cross portion of the forehead support830, e.g., under the base 834 and over respective arm bars 836 as shownin FIG. 4-14. One or more portions of the forehead support (e.g., armbars) may be over-molded (e.g., with silicone) to help retain the upperstraps in position. Such arrangement reduces parts and allows the strapsto nest in the forehead support as illustrated. However, the upper crossportion of the t-shaped forehead support may have other suitableconfigurations, e.g., arms with slots to receive respective headgearstraps.

As shown in FIG. 4-17, one or more flexible ribs 837 may be providedalong the movement region 835 of the forehead support. The flexible ribs837 may be made from a more flexible material (e.g., such asSantoprene™, silicone, etc.) than the remainder of the forehead supportto enable greater adjustment of the movement region. In an embodiment,the ribs may be co-molded over the movement region and/or embeddedwithin the thickness of the movement region (e.g., one or more notchesor cut-outs provided along length of movement region and then notchesfilled with more flexible material to modify flexibility).

In an alternative embodiment, as shown in FIG. 4-18, the foreheadsupport may be detachably connected to the frame. As illustrated, thebase of the forehead support 930 (e.g., constructed of a titanium alloy)may include a resilient clip portion 939 that is structured toresiliently deflect into a cavity 925 provided to the base of the frame920, e.g., with a snap-fit.

The movement region 835 allows coarse adjustment (e.g., larger tuningmovement) and fine adjustment (e.g., smaller or minute tuning movement)of the cushion 840 provided to the frame 820. As shown in FIG. 4-15,coarse adjustment may be achieved by adjusting the headgear straps toachieve fit. That is, the movement region preloads the forehead supportsuch that it is positioned away from the patient's forehead in itsrelaxed state (see dashed lines in FIG. 4-15). The upper headgear strapscan then be tightened to pull the forehead support towards the patient'sforehead (see solid lines in FIG. 4-15), which tightening will translateforces down the forehead support and into the movement region, and thusforce the cushion into the patient's face.

As shown in FIG. 4-16, fine adjustment may be achieved by manipulating(or automatic adjustment inherent to the amount of force deflectionbuilt into the movement region 835) the movement region 835 to applylight pressure to the cushion to achieve comfort and seal. That is, theframe and cushion may be manipulated or flexed relative to the foreheadsupport (which remains relatively fixed in position relative to thepatient) to adjust the position of the cushion for enhanced comfort andseal (as indicated by dashed and solid lines in FIG. 4-16).

In an embodiment, the location of the movement region of the foreheadsupport along a lower region of the frame may allow the forehead supportto force the frame into the patient's face without the use of lowerheadgear straps. However, lower headgear straps may be connected to theframe to enhance the seal of the cushion. For example, as shown in FIGS.4-15 and 4-16, lower strap connectors 829 (e.g., headgear clipreceptacles or slots) may be positioned along lower sides of the frame820, e.g., to anchor the movement region 835 on the patient's face.

1.3 Elbow Module

As best shown in FIGS. 2 and 5-1 to 5-3, the elbow module 70 includes aninterfacing structure 72 structured to interface or otherwise attach tothe cushion module 40, an elbow 74 provided to one end 72(1) of theinterfacing structure 72, and a vent arrangement 76 provided to theother end 72(2) of the interfacing structure 72 for gas washout. Asillustrated, the elbow module 70 provides a relatively low profile withreduced bulk.

The elbow module 70 may be constructed of a relatively rigid materialsimilar to the main body 42 of the cushion module 40 (e.g.,polycarbonate) or the elbow module 70 may be constructed of a softermaterial (e.g., TPE or silicone). In an embodiment, the elbow module 70may be constructed of a material in the range of about 60-100 durometer,e.g., 80 durometer.

In an embodiment, the vent arrangement 76 and elbow 74 may beconstructed of different materials, e.g., specific to vent and elbowfunctions. Also, the elbow module 70 may include overmolding, texturing,and/or flocking, e.g., similar to the frame module 20 described above.

The elbow module 70 pairs vent flow with impedance. This allows ventflow and/or impedance to be optimally designed or changed by alteringthe elbow module. That is, one piece may be changed to change the ventarrangement and/or the elbow size, e.g., if requirements change for thePAP (positive airway pressure) device. In addition, the vent arrangement76 is fixed and positioned away from the elbow outlet 75 so that theoutlet will not impede vent flow and vice versa, e.g., to provideoptimal gas washout.

In the illustrated embodiment, the ends 72(1), 72(2) of the interfacingstructure 72 are sloped or angled with respect to one another as bestshown in FIG. 5-3. This arrangement may help to orient the direction ofthe vent arrangement and/or elbow.

In an embodiment, the mask system may be provided with a number ofdifferent elbow modules 70, e.g., each having a vent arrangement and/orelbow of different styles and/or sizes. For example, each elbow modulemay include structure as required for different operating pressures.This provides a modular arrangement that allows the cushion module 40 tobe selectively and removably coupled to one of multiple elbow modules70.

1.3.1 Elbow

The elbow 74 includes a first portion 74(1) provided to the interfacingstructure 72 and a second portion 74(2) provided to a swivel joint 80adapted to be connected to an air delivery tube. In the illustratedembodiment, the second portion 74(2) includes snap-fit tabs to connectthe second portion 74(2) to the swivel joint 80. As illustrated, theelbow may taper from a larger internal diameter at the second portion74(2) to a smaller internal diameter at the first portion 74(1).

1.3.2 Vent Arrangement

The vent arrangement 76 is positioned on a relatively flat portion 77 ofthe interfacing structure 72. Moreover, the relatively flat portion 77is recessed with respect to the peripheral edge of the interfacingstructure 72. As illustrated, the relatively flat portion 77 has agenerally oval shape. However, the interfacing structure 72 may includeother suitable structure to support the vent arrangement 76, e.g.,contoured surface, concave surface, etc.

In the illustrated embodiment, the vent arrangement 76 includes aplurality of holes 78 arranged in a five column pattern. The five columnpattern includes a center column, flanked by intermediate columns, whichin turn are flanked by outside columns. As illustrated, the columns aresubstantially aligned or parallel to a longitudinal axis of the elbow.

The center column includes 3-20 holes, e.g., 9 holes, the intermediatecolumns each include 3-20 holes, e.g., 8 holes, and the outside columnseach include 3-20 holes, e.g., 5 holes. As illustrated, the holes in thecenter column are offset with the holes in the intermediate columns.Also, holes in the center column are aligned with the holes in theoutside columns, with the center column having two additional holes atthe upper and lower ends.

In the illustrated embodiment, each hole may have a generally part conicshape, including opposed walls that converge from a larger (inside)diameter to a smaller (outside) diameter, as viewed in the direction ofexhausted gas. However, other hole configurations are possible, e.g.,larger (outside) diameter and smaller (inside) diameter.

However, it should be appreciated that the vent arrangement 76 mayinclude other suitable hole arrangements, hole numbers, and/or holeshapes.

1.3.3 Elbow Module Attachment to Cushion Module

The main body 42 of the cushion module 40 is structured to maintain theelbow module 70 in an operative position with respect to the patient'sface.

In the illustrated embodiment, the opening 46 of the main body 42includes a flange or interfacing structure 47 along its peripheral edgethat is adapted to interface with or otherwise removably connect to theinterfacing structure 72 of the elbow module 70. The interfacingstructures 47, 72 may connect with a friction fit, snap-fit, mechanicalinterlock, or other suitable attachment mechanism. However, othersuitable arrangements for attaching the elbow module 70 to the cushionmodule 40 are possible.

The opening 46 of the cushion module 40 and the interfacing structure 72of the elbow module 70 include complementary shapes. In the illustratedembodiment, the opening 46 and interfacing structure 72 each include afigure-8 or hourglass-type shape. Such shape allows the elbow module 70to be attached to the cushion module 40 in one of only two orientations.This allows the patient to select between two routings of the airdelivery tube.

1.3.4 Alternative Tube Routings

The elbow module 70 may be attached to the cushion module 40 in a firstorientation (as shown in FIGS. 1-1 to 1-3) so that the elbow extendsdownwardly from the mask to direct the air delivery tube under thepatient's head in use. Alternatively, the elbow module 70 may be rotatedand attached to the cushion module 40 in a second orientation (as shownin FIG. 6) so that the elbow extends upwardly from the mask to directthe air delivery tube over the patient's head in use.

The different orientations of the elbow module 70 may also change thedirection of vent flow from the vent arrangement 76. For example, in thesecond orientation of the elbow module 70 (FIG. 6), the vent arrangement76 may direct vent flow generally towards the patient, which may be lessobtrusive to the patient's bed partner. Also, the different orientationsof the elbow module 70 allows different washout configurations withoutusing a baffle.

1.3.5 Elbow Module Seal

In an embodiment, a seal may be provided at the interface between theelbow module 70 and the cushion module 40, e.g., around the opening 46of the cushion module 40. For example, a seal (e.g., elastomeric,ring-shaped seal) may be formed separately from the elbow module 70 andthe cushion module 40 and attached at the interface between the elbowmodule 70 and the cushion module 40 (e.g., sandwiched between elbowmodule/cushion module connection, adhesive, etc.). Alternatively, a sealmay be co-molded with one of the elbow module 70 and cushion module 40.For example, the elbow module 70 may be molded of a material (e.g.,polycarbonate) and the seal may be co-molded onto the elbow module 70 ofa relatively soft elastomeric material (e.g., TPE, silicone). In anotherembodiment, the elbow module 70 and/or cushion module 40 may includeoverlapping material to provide a seal, e.g., elbow module includesoverlapping material that overlaps frame module at the interface toprovide a seal.

1.3.6 Alternative Elbow/Vent Arrangement

In an alternative embodiment, the elbow module may be replaced withseparate vent and elbow modules. In such arrangement, as shown in FIG.7, the main body 42 of the cushion module 40 may include a pair ofopenings 46.1, 46.2, one to receive a vent module 176 and one to receivean elbow module 174. The vent module 176 and elbow module 174 may bestructured to rotate or swivel with respect to the main body 42. Also,the vent module 176 and/or elbow module 174 may be constructed ofrelatively soft or hard material, and may include a seal at theinterface with the main body 42.

In another embodiment, the elbow module may be flexibly attached to thecushion module to allow the elbow module to move freely thereby reducingtube drag affects.

For example, as shown in FIGS. 8-1 and 8-2, a flexible gusset 650 may beprovided between the elbow module 670 and the main body 642 of thecushion module 640. As illustrated, the gusset 650 is constructed of aflexible material (e.g., elastomeric) and is contoured or bent along itslength (i.e., gusset 650 extends upwardly from its connection to themain body 642) in order to allow a range of axial and lateral movement.That is, the gusset 650 adds flexibility and articulation of the elbowmodule in use, e.g., to reduce tube drag.

Thus, when the tube forces the elbow module to move, the gusset willabsorb the force thereby decreasing the risk of altering the position ofthe cushion module with respect to the patient's face and potentiallydisrupting the seal. FIG. 8-1 illustrates an initial position of theelbow module 670 (i.e., the position when no force is applied to theelbow module, e.g., by the tube), and FIG. 8-2 illustrates a deflectedposition of the elbow module 670 (i.e., the position when force isapplied to the elbow module, e.g., by the tube). As illustrated, thegusset 650 bends or deforms without affecting the cushion module 640.

In yet another embodiment, a series of gussets may be provided betweenthe elbow module and the cushion module. For example, as shown in FIG.9, a concertina or bellows arrangement 750 may be provided between theelbow module 770 and the main body 742 of the cushion module 740, e.g.,to absorb tube drag forces. As illustrated, the concertina arrangementincludes a series of folds that allows a range of axial and lateralmovement.

It should be appreciated that such flexible gusset may be used to attachan elbow to a mask frame.

While the invention has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.Furthermore, each individual component of any given assembly, one ormore portions of an individual component of any given assembly, andvarious combinations of components from one or more embodiments mayinclude one or more ornamental design features. In addition, while theinvention has particular application to patients who suffer from OSA, itis to be appreciated that patients who suffer from other illnesses(e.g., congestive heart failure, diabetes, morbid obesity, stroke,bariatric surgery, etc.) can derive benefit from the above teachings.Moreover, the above teachings have applicability with patients andnon-patients alike in non-medical applications.

What is claimed is:
 1. A mask system, comprising: a frame module; and acushion module provided to the frame module and adapted to form a sealwith the patient's face, wherein the cushion module includes a main bodydefining a breathing chamber and adapted to interface with the framemodule and a cushion adapted to form a seal with the patient's face, themain body and the cushion being comolded with one another.
 2. A masksystem according to claim 1, wherein the frame module includes headgearconnectors adapted to removably attach to respective headgear straps ofheadgear.
 3. A mask system according to claim 1, wherein the framemodule includes a forehead support, the forehead support providingheadgear connectors adapted to removably attach to respective headgearstraps of headgear.
 4. A mask system according to claim 3, wherein theforehead support is fixed in position.
 5. A mask system according toclaim 1, wherein the frame module includes open construction thatprovides an annular cushion retaining portion structured to retain thecushion module.
 6. A mask system according to claim 1, wherein thecushion is a nasal cushion.
 7. A mask system according to claim 1,wherein the main body is constructed of a relatively rigid material andthe cushion is constructed of a relatively soft elastomeric material. 8.A mask system according to claim 7, wherein the main body is constructedof polycarbonate and the cushion is constructed of silicone.
 9. A masksystem according to claim 1, wherein the cushion module is attachable tothe frame module in different angular positions with respect to theframe module.
 10. A mask system according to claim 9, wherein thecushion module is pivotally mounted to the frame module.
 11. A masksystem according to claim 1, further comprising an elbow module adaptedto be connected to an air delivery tube that delivers breathable gas tothe patient.
 12. A mask system according to claim 11, wherein the elbowmodule is provided to the cushion module.
 13. A mask system according toclaim 12, wherein the elbow module includes an interfacing structurestructured to interface with the cushion module, an elbow provided toone end of the interfacing structure, and a vent arrangement provided tothe other end of the interfacing structure for gas washout.
 14. A masksystem according to claim 13, wherein the vent arrangement includes aplurality of holes.
 15. A mask system according to claim 13, wherein theinterfacing structure is structured to interface with an openingprovided to the main body of the cushion module.
 16. A mask systemaccording to claim 15, wherein the interfacing structure and the openingof the cushion module include complementary shapes.
 17. A mask systemaccording to claim 16, wherein the interfacing structure and the openingof the cushion module include a figure-8 or hourglass-type shape.
 18. Amask system according to claim 12, wherein the elbow module isattachable to the cushion module in two different orientations.
 19. Amask system according to claim 18, wherein the elbow module isattachable to the cushion module in (1) a first orientation so that theelbow extends downwardly from the mask to direct the air delivery tubeunder the patient's head in use, and (2) a second orientation so thatthe elbow extends upwardly from the mask to direct the air delivery tubeover the patient's head in use.
 20. A mask system according to claim 12,further comprising a seal provided at the interface between the elbowmodule and the cushion module.